<?php
// 应用公共文件
function getColumn($column){
	$letter2 = [
		'Z',"A","B","C","D","E","F","G",
		"H","I","J",'K','L','M','N',
		'O','P','Q','R','S','T',
		'U','V','W','X','Y'
	];
	$letter1 = [
		'',"A","B","C","D","E","F","G",
		"H","I","J",'K','L','M','N',
		'O','P','Q','R','S','T',
		'U','V','W','X','Y','Z'
	];
	$m = floor($column/26);
	$n = $column%26;
	if($n==0){
		$m-=1;
	}
	return $letter1[$m].$letter2[$n];
}